[app] Fix overlays stuck on #218

The logic to check bounding box is a bit complicated in the shared module
as it's different for the CLI vs. config file. This changes it to make the
differences more clear, and also updates the flag value from False to True.
This simplifies checks, and also allows us to fallback so that if the value
is not a boolean, we can assume the user specified smoothing time via the
`-bb` CLI flag (in which case the config option is overriden). When the `-bb`
flag is set alone, or from the UI, the bounding-box-smooth-time setting
is used as expected.

Author: Breakthrough

docs/changelog.md

@@ -346,6 +346,7 @@ This version of DVR-Scan includes a new, faster background subtraction algorithm
 
 ### In Development
 
+ * [bugfix] Fix bounding box overlay stuck on when using the OpenCV output mode [#213](https://github.com/Breakthrough/DVR-Scan/issues/209)
  * [feature] various UI enhancements:
      * input videos can now be sorted
      * add button to open log folder

dvr_scan/cli.py

@@ -370,7 +370,7 @@ def get_cli_parser(user_config: ConfigRegistry):
         metavar="smooth_time",
         type=timecode_type_check("smooth_time"),
         nargs="?",
-        const=False,
+        const=True,
         help=(
             "If set, draws a bounding box around the area where motion was detected. The amount"
             " of temporal smoothing can be specified in either frames (12345) or seconds (number"

dvr_scan/shared/__init__.py

@@ -138,21 +138,23 @@ def init_scanner(
         )
 
     bounding_box = None
-    # bounding_box_arg will be None if -bb was not set, False if -bb was set without any args,
-    # otherwise it represents the desired smooth time.
-    bounding_box_arg = settings.get_arg("bounding-box")
-    if bounding_box_arg is not None or settings.get("bounding-box"):
-        if bounding_box_arg is not None and bounding_box_arg is not False:
-            smoothing_time = FrameTimecode(bounding_box_arg, scanner.framerate)
-        else:
-            smoothing_time = FrameTimecode(
-                settings.get("bounding-box-smooth-time"), scanner.framerate
-            )
+
+    # NOTE: The CLI overloads the type of the bounding-box setting by allowing an optional smooth
+    # time. When set, this means the flag is no longer boolean, and represents desired smoothing.
+    bounding_box_option_is_smoothing = not isinstance(settings.get("bounding-box"), bool)
+    bounding_box_enabled = bool(settings.get("bounding-box")) or bounding_box_option_is_smoothing
+    if bounding_box_enabled:
+        smoothing_time = (
+            settings.get("bounding-box")
+            if bounding_box_option_is_smoothing
+            else settings.get("bounding-box-smooth-time")
+        )
+        smoothing = FrameTimecode(smoothing_time, scanner.framerate).frame_num
         bounding_box = BoundingBoxOverlay(
             min_size_ratio=settings.get("bounding-box-min-size"),
             thickness_ratio=settings.get("bounding-box-thickness"),
             color=settings.get("bounding-box-color"),
-            smoothing=smoothing_time.frame_num,
+            smoothing=smoothing,
         )
 
     scanner.set_overlays(